Study On Treatment Of Dyeing Wastewater By Hydrolytic-Aerobic Moving Bed Bio-Film Process

There are characteristics of high concentration contaminants, complex composition and variational water quality in dye-printing wastewater, which has become the one of the most important and difficult for treating wastewater due to the high expense by physico-chemical method and low removal efficiency only by biological method. A new kind of process of hydrolysis-acidificating/aerobic moving-bed biofilm was used to treat dyeing wastewater in this dissertation. The aim is to search an available technique.The experimental wastewater is supplied by some printing and dying company in Harbin. The first stage hydrolysis-acidificating moving Bed Biofilm reactor (MBBR) of this experiment can improve the property of biodegradation in wastewater and create a favorable condition for the latter stage MBBR of aerobic oxidation. The parameters such as COD, BOD5, pH, chromaticity, SS, DO etc have been monitored, controlled and studied.The first stage of this study is to complete biofilm colonization on packing material and starting-up and acclimation. After 60 days of starting up and acclimation, with intermittent sludge-removal method, it can be found by surveying that surface coatings grew well and removal efficiency of COD and chromaticity kept stable.The second stage is to optimize operation parameters for hydrolysis- acidification/aerobic MBBR of wastewater treatment. The experimental results showed the optimal operation condition is following: the HRT in hydrolysis- acidification/aerobic MBBR are both 8 hours, hydrolysis and acidification reactor can run in ambient temperature and aerobic MBBR must be controlled at 20℃, the concentration of dissolved oxygen in hydrolysis process and acidification is limited below 0.5 mg·L-1 and about 3~5mg·L-1 in aerobic MBBR. In this condition the COD and chromaticity removal efficiencyes can respectively reach up to 85% and system keep stable.A coupling processs of CWAO+hydrolysis-acidification/aerobic MBBR is also studied to treat dying wastewater. The experimental results showed that the COD and chromaticity removal efficiencyes were improved respectively, and it is apt to high concentration dying wastewater treatment. The qualities of effluent...